DTC U129E: F-CAN Malfunction (Powertrain Control Module (PCM)-Power Control Unit (PCU)) (2016-18)

General Description

Courtesy of HONDA, U.S.A., INC.

The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (F-CAN_H and F-CAN_L). When the powertrain control module (PCM) does not receive the signals from the keyless access/TPMS control unit via the F-CAN lines for a set time, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status

Execution	Continuous
Sequence	None
Duration	1.5 seconds or more
DTC Type	One drive cycle, MIL off
OBD Status	PASSED/FAILED/NOT COMPLETED (STILL TESTING)

Enable Conditions

Condition	Minimum	Maximum
Battery voltage [BATTERY]	10.0 V	-

[ ]: HDS Parameter

Malfunction Threshold

The PCM does not receive any signals via the F-CAN lines for at least 1.5 seconds.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Keyless access/TPMS control unit failure (include fuse fall-outs)
F-CAN circuit F-CAN_H line open
F-CAN circuit F-CAN_L line open
F-CAN circuit F-CAN_H line short to ground
F-CAN circuit F-CAN_L line short to ground
PCM internal circuit failure

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected, a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC

The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.